A question on tire installation.

RCtime · 01-13-2009, 05:18 AM

Tomorrow morning I will have new tires installed on my Journey.
They have some fairly large floor jacks they will use to lift the wheels off the ground.
I want to be very observant as to where they are going to place the jacks lift points.
Would in the rear under the axle housing or frame be better.
In the front same question.
Should I use the hwh jacks at all. They will just be lifting a corner at a time I believe.
Thanks Ron

RCtime · 01-13-2009, 05:18 AM

Tomorrow morning I will have new tires installed on my Journey.
They have some fairly large floor jacks they will use to lift the wheels off the ground.
I want to be very observant as to where they are going to place the jacks lift points.
Would in the rear under the axle housing or frame be better.
In the front same question.
Should I use the hwh jacks at all. They will just be lifting a corner at a time I believe.
Thanks Ron

smlranger · 01-13-2009, 06:30 AM

I had my new tires installed at a truck tire shop and they used a big rolling floor jack. I believe they placed the jack under the axles to raise the coach.

They did have the dickens of a time getting the rear wheels separated due to corosion/electrolysis between the alum and steel wheels. They banged, cussed, etc. but finally got them apart. I believe they coated the wheels with an anti seize compound when they put them back on.

MrTransistor · 01-13-2009, 07:49 PM

Just a note, make sure that when they mount the new tires, they don’t inflate them to seat the bead then continue airing them up to full pressure. Proper procedure is to seat the bead, then let ‘ALL’ the air out so the tire can center it’s self on the rim, then inflate to full pressure. This makes a big difference with tire balance. Proper mounting will probably let you run with no wheel weights. Improper mounting will probably not balance at all.

SeeTheUSA · 01-14-2009, 02:23 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by MrTransistor:
Just a note, make sure that when they mount the new tires, they don’t inflate them to seat the bead then continue airing them up to full pressure. Proper procedure is to seat the bead, then let ‘ALL’ the air out so the tire can center it’s self on the rim, then inflate to full pressure. This makes a big difference with tire balance. Proper mounting will probably let you run with no wheel weights. Improper mounting will probably not balance at all. </div></BLOCKQUOTE>

Back in my early years, when my work involved lots and lots of tire mounting/dismounting, big and small, I recall a similar practice as related to inner tubes --- inflate to spread out the tube in the tire, then deflate to allow the tube to nestle inside the tire evenly, then re-inflate to the proper PSI.

I'm trying to envision what you've suggested about today's tires --- allowing them to center --- and I must admit it makes no sense to me, particularly as related to balancing. Perhaps it's just too technical for me.

lthrnk · 01-14-2009, 02:34 AM

I'm sure your tire guy will tell you but just in case not. Be sure to go back there and get the lug nuts re-torqued after you have driven the coach around 50 miles.

TXiceman · 01-14-2009, 02:45 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I'm trying to envision what you've suggested about today's tires --- allowing them to center --- and I must admit it makes no sense to me, particularly as related to balancing. Perhaps it's just too technical for me. </div></BLOCKQUOTE>

Makesd sense on a tube type tire, but on a tubeless, once the bead has pushed on to the rim, it will not move unitl, you break the bead from the rim. Deflating is an hold over from tube type tires that is now usless.

ken

MrTransistor · 01-14-2009, 09:39 PM

Answer,

Michelin says that their tires, when mounted properly, should not require balancing. This is quite true, as I have found out. The problem is that when the tire is inflated to seat it on the rim, it does not usually press outward evenly on the rim but instead one side will seat first then the rest of the bead will pop into place. This causes the bead to be slightly off center with respect to the wheel. I suppose you could get lucky and have a perfectly opposite imbalance but that would rarely happen.

This slight off center will cause the tire to be out of round and out of balance. The heavy side of the wheel assembly will also be the side that is high making it almost impossible to get rid of the shaking. Our RV has Michelin tires and after paying to have the fronts spin balanced on the coach, the shaking was still there. My solution was to jack the front end up as high as the HWH’s would go, then release all the air from each tire, wait about 5 minutes, then re-inflate both tires.

Bingo, no more shaking. I even removed the 16 Oz. of weight that the outfit had used trying to get them to dynamically balance. Problem was, they were still out of round until I re-seated them. After this success, I did the same procedure with the rears and they smoothed out as well.

The Michelin brochures have the same procedure recommended for mounting tires but most shops, pressed for time, just mount the tire and pump it up. Our tires now have close to 80,000 miles on them and seem like there is at least another 50,000 miles of tread left on them. When we finally replace the tires, I will stay with Michelin XZE’s, and I will make sure the proper mounting procedure is observed.

DAN L · 01-14-2009, 11:22 PM

i would use the hwh jacks and lift the coach evenly to avoid twisting the chassis. you can pop windshields out if you twist the chassis enough.
use a jackstand for safety under the axle on the wheels that are removed.

SeeTheUSA · 01-15-2009, 03:10 AM

There is some support of MrTransistor's discussion in a couple of Michelin's videos found here:

http://tinyurl.com/7cyop3

Watch the "Proper Mounting Techniques using T-45 Tire Irons" and "Runout & Match Mounting" videos.

Thanks Mark --- wow, just everything is more complex than it seems!

Displaced Connecticut Yankee · 01-15-2009, 04:39 AM

When I was doing tire installations (a loooong loooong time ago), we didn't install the valves until the tire had been mounted. The tire was "popped" onto the rim with the valve removed, which meant that it alway had to deflate when we removed the air hose. THEN we installed the valve into the valve stem.

Tom N · 01-15-2009, 04:43 AM

RCtime · 01-15-2009, 05:02 AM

The new tires are on and the install was pretty smooth. They used equal balancer in the front tires only.
One thing I did learn was the damage that UV, exposure can do to a tire.
All 4 outside tires had moderate to severe weather checking/cracks on the sidewalls, while the 2 inside duals looked like they could run another 7 years. They looked perfect.
I just in my mind cannot understand how this equal works. They tossed 2 bags inside each front tire.
The drive back to my storage area was not that much different than before though as it was only about 12 miles on surface streets and hardly over 40 mph at the most at times.